JP2013194697A - Vane pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vane pump capable of suppressing increase in drive loss caused by a check valve which opens/closes a discharge port.SOLUTION: A vane pump used as a fluid pressure supply source includes a check valve 70 which is opened with respect to the flow of a hydraulic fluid discharged from a discharge port 32 to a high pressure chamber 35. The check valve 70 includes: a valve element 71 which is abutted on a back surface 37 where the discharge port 32 is opened in a side plate 30, and closes the discharge port 32; a plurality of pins 81 protruding from a back surface 74 of the valve element 71; a guide hole 11 which is formed to be opened while facing the high pressure chamber 35 and into which the pins 81 are inserted in a freely slidable manner; and a spring (energizing means) 82 which is accommodated in the high pressure chamber 35 and presses the valve element 71 to the side plate 30.

Description

  The present invention relates to a vane pump used as a fluid pressure supply source.

  In this type of vane pump, vanes are housed in a plurality of slits that open radially to the rotor. Each vane is urged in the direction protruding from the slit by the oil pressure of the vane back pressure chamber that presses the base end portion and the centrifugal force that works as the rotor rotates, and the tip end portion of the vane is the inner periphery of the cam ring. Touch the cam surface. As the rotor rotates, the vane slidingly contacting the inner circumferential cam surface reciprocates, the pump chamber expands and contracts, and the hydraulic oil pressurized in the pump chamber is discharged from the discharge port that opens in the side plate to the high pressure in the vane pump. It is discharged into the chamber and supplied from this high pressure chamber to the hydraulic equipment.

  In such a vane pump, when the rotation of the rotor continues to stop, the vane at the top of the rotor falls into the slit due to gravity. For this reason, there is a possibility that the operation of the vane protruding from the slit at the time of startup is delayed and the increase of the pump discharge pressure is delayed.

  As a countermeasure against this, the vane pump (blade-type rotary pump) disclosed in Patent Document 1 has a discharge plate (conveying holes 21 and 23) and a vane back pressure in the slit on the pressure plate (11) on which the rotor (7) slides. Two grooves (35, 37) communicating with the chamber (lower blade region) are provided, and a cold start plate (17) defining a flow communication portion is provided between the grooves (35, 37). Yes. The cold start plate (17) is pressed against the pressure plate (11) by the pressing spring (19). As the pressing spring (19), a leaf spring formed in a curved plate shape is used.

  During startup, the cold start plate (17) biased by the pressing spring (19) contacts the pressure plate (11) to define a flow communication portion. Accordingly, the hydraulic oil discharged from the discharge port is supplied to the vane back pressure chamber through the flow communication portion, and the vane that has fallen into the slit due to gravity when stopped is prompted to protrude from the slit.

  After startup, the cold start plate (17) moves away from the groove (35, 37) against the pressing spring (19) as the pressure at the discharge port increases. As a result, the hydraulic oil discharged from the discharge port is supplied from the grooves (35, 37) to the hydraulic equipment.

  The cold start plate (17) also functions as a check valve that opens with respect to the flow of the working fluid discharged from the discharge ports (conveying holes 21, 23).

JP-A-9-119383

  However, the vane pump (blade-type rotary pump) has a configuration in which the cold start plate (17) is pressed against the pressure plate (11) by a pressure spring (19) made of a leaf spring, and thus the pressure plate (11) during normal operation. ) Is difficult to sufficiently separate from the cold start plate (17), and the driving loss of the pump increases due to the resistance of the pressure plate (11) to the flow of hydraulic oil.

  The present invention has been made in view of the above problems, and an object thereof is to provide a vane pump that can suppress an increase in driving loss due to a check valve that opens and closes a discharge port.

  The present invention is a vane pump used as a fluid pressure supply source, which is a rotor that is rotationally driven, a plurality of slits that are radially formed in the rotor, and a plurality of vanes that are slidably received in the slits. An inner peripheral cam surface with which the tip of the vane is in sliding contact, a pump chamber defined between the inner peripheral cam surface and the adjacent vane, and a suction port for guiding the working fluid sucked into the pump chamber A discharge port that guides the working fluid discharged from the pump chamber, a side plate that opens the discharge port, a high-pressure chamber that guides the working fluid discharged from the discharge port to a fluid pressure supply destination, and a discharge port to the high-pressure chamber. A check valve that opens with respect to the flow of the discharged working fluid, and the check valve is in contact with the back surface of the side plate where the discharge port opens to close the discharge port. Plural pins projecting from the back of the valve body, guide holes formed so as to open facing the high pressure chamber, and the pins are slidably inserted, and accommodated in the high pressure chamber to press the valve body against the side plate And an urging means.

  In the present invention, the plurality of pins slide in the guide holes, so that the valve body moves while maintaining the posture with respect to the side plate, and a sufficient stroke for the valve body to move with respect to the side plate is ensured. As a result, a sufficient cross-sectional area of the flow path defined between the valve element and the side plate when the check valve is opened is secured, and an increase in driving loss of the vane pump due to the check valve can be suppressed.

It is a circuit diagram which shows the flow of the hydraulic fluid at the time of normal operation of the vane pump which concerns on embodiment of this invention. It is a circuit diagram which shows the flow of the hydraulic fluid at the time of starting of the vane pump which concerns on embodiment of this invention. It is sectional drawing of the vane pump which concerns on embodiment of this invention. It is a front view of the vane pump concerning the embodiment of the present invention. It is a front view of the side plate which concerns on embodiment of this invention. It is a rear view of the pump cover which concerns on embodiment of this invention. It is sectional drawing which shows the valve closing state of the non-return valve which concerns on embodiment of this invention. It is sectional drawing which shows the valve opening state of the non-return valve which concerns on embodiment of this invention. It is a rear view which shows the check valve and side plate which concern on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  The vane pump 1 shown in FIGS. 1A and 1B is used as a hydraulic pressure supply source that supplies hydraulic oil stored in a tank 26 to a hydraulic device (fluid pressure supply destination) 18. The hydraulic device 18 is, for example, a transmission or a power steering device mounted on the vehicle.

  The vane pump 1 uses a working oil (oil) as a working fluid, but a working fluid such as a water-soluble alternative liquid may be used instead of the working oil.

  As shown in FIG. 2, in the vane pump 1, the power of an engine or an electric motor (not shown) is transmitted to the end of the drive shaft 9, and the rotor 2 connected to the drive shaft 9 rotates. The rotor 2 rotates in the clockwise direction as indicated by an arrow in FIG.

  The pump body 10 is formed with a pump housing recess 10A in which the rotor 2, the cam ring 4, the side plate 30 and the like are housed. A pump cover 60 is fastened to the pump body 10, and the pump housing recess 10 </ b> A is sealed by the pump cover 60. The drive shaft 9 is rotatably supported by the pump body 10 and the pump cover 60.

  The configuration is not limited to this, and the cam ring 4 and the side plate 30 may be integrally formed with the pump body 10.

  As shown in FIG. 3, a plurality of vanes 3 are interposed between the cam ring 4 and the rotor 2. In the rotor 2, a plurality of slits 8 are formed radially with a predetermined interval. The vane 3 is formed in a rectangular plate shape and is slidably inserted into the slit 8.

  A vane back pressure chamber 6 is defined between the slit 8 and the base end of the vane 3, and pump discharge pressure is guided to the vane back pressure chamber 6. The vane 3 is urged in a direction protruding from the slit 8 by the pressure of the vane back pressure chamber 6 that presses the base end portion thereof and the centrifugal force that works as the rotor 2 rotates, and the tip end portion of the vane 3 is cam ring 4. In contact with the inner peripheral cam surface 5.

  Inside the cam ring 4, a plurality of pump chambers 7 are defined by the inner peripheral cam surface 5 of the cam ring 4, the outer periphery of the rotor 2, and the adjacent vanes 3. As the rotor 2 rotates, the vane 3 slidably contacting the inner peripheral cam surface 5 reciprocates, and the pump chamber 7 expands and contracts. As a result, the hydraulic oil is sucked into the pump chamber 7 from the first suction port 31 and the second suction port 33 through the suction passage 25 as indicated by arrows in FIG. Is discharged from the discharge ports 32 and 34 into the high-pressure chamber 35.

  The cam ring 4 is an annular member in which the inner peripheral cam surface 5 has a substantially oval shape. As the rotor 2 makes one revolution, each vane 3 following the inner peripheral cam surface 5 reciprocates twice.

  The balanced vane pump 1 includes a first suction region and a first discharge region in which the vane 3 reciprocates for the first time, a second suction region and a second discharge in which the vane 3 reciprocates for the second time. A region. In the first and second suction regions, the volume of the pump chamber 7 expands as the rotor 2 rotates. In the first and second discharge regions, the volume of the pump chamber 7 contracts as the rotor 2 rotates. Between the first suction region, the first discharge region, the second suction region, and the second discharge region, there is a transition region where the direction in which the vane 3 moves in the radial direction of the rotor 2 is switched.

  On the inner circumferential cam surface 5 of the cam ring 4, the first suction section 5 </ b> A, the first suction / discharge transition section 5 </ b> B, in which the working oil is sucked through the first suction port 31 with the rotation of the rotor 2, The first discharge section 5C in which the hydraulic oil is discharged through the discharge port 32, the discharge suction transition section 5D, the second suction section 5E in which the hydraulic oil is sucked in through the second suction port 33, and the second suction A discharge transition section 5F, a second discharge section 5G through which hydraulic oil is discharged through the second discharge port 34, and a discharge suction transition section 5H are formed.

  The first suction port 31 and the first suction section 5A are arranged in the first suction region. The first discharge port 32 and the first discharge section 5C are arranged in the first discharge area. The first suction / discharge transition section 5B is disposed between the first suction section 5A and the first discharge section 5C. The second suction port 33 and the second suction section 5E are arranged in the second suction region. The discharge / suction transition section 5D is disposed between the first discharge section 5C and the second suction section 5E. The second discharge port 34 and the second discharge section 5G are arranged in the second discharge region. The second suction / discharge transition section 5F is disposed between the second suction section 5E and the second discharge section 5G. The discharge suction transition section 5H is disposed between the second discharge section 5G and the first suction section 5A.

  The pump cover 60 has a rotor front side end surface 69 in which the rotor 2 and the vane 3 are in sliding contact. The rotor 2 has front and rear end surfaces 21 and 22 orthogonal to the rotation center axis, and the front end surface 21 is in sliding contact with the rotor front end surface 69 of the pump cover 60. The rear end surface 22 of the rotor 2 is in sliding contact with the rotor rear end surface 38 of the side plate 30.

  In addition, the rotor front side end surface with which the rotor 2 is slidably contacted is not limited to the configuration described above, and may be configured such that a side plate (not shown) is provided separately from the pump cover 60.

  As shown in FIG. 1A, the first suction port 31 and the second suction port 33 communicate with the tank 26 through the suction passage 25, and hydraulic oil from the tank 26 is guided.

  A high pressure chamber 35 is defined between the bottom of the pump housing recess 10 </ b> A of the pump body 10 and the side plate 30. A first discharge port 32 and a second discharge port 34 are opened in the high pressure chamber 35. The high pressure chamber 35 constitutes a part of a discharge passage 36 that communicates the discharge ports 32, 34 and the hydraulic equipment 18.

  The rotor rear end surface 38 of the side plate 30 is pressed against the rear end surface of the cam ring 4 by the pump discharge pressure guided to the high pressure chamber 35.

  When the vane pump 1 is operated, the vane 3 is urged in a direction protruding from the slit 8 by the hydraulic oil pressure in the vane back pressure chamber 6 that presses the base end of the vane pump 1 and the centrifugal force that works as the rotor 2 rotates. Then, the tip end portion is in sliding contact with the inner peripheral cam surface 5 of the cam ring 4.

  As shown in FIG. 4, the rotor rear end surface 38 of the side plate 30 has a first suction port 31, a second suction port 33, a first discharge port 32, and a second discharge port 34. Four back pressure ports 41 to 44 are opened. The back pressure ports 41 to 44 extend side by side in an arc shape centering on the rotation axis of the rotor 2, and communicate with the vane back pressure chambers 6. Each of the back pressure ports 41 to 44 is disposed in the first suction region, the first discharge region, the second suction region, and the second discharge region, respectively.

  The side plate 30 has a discharge pressure introduction passage 51 that communicates the high pressure chamber 35 and the back pressure port 41 in the first suction region, and a discharge that communicates the high pressure chamber 35 and the back pressure port 43 in the second suction region. A pressure introducing passage 53 is formed. Thereby, when the vane pump 1 is operated, the pump discharge pressure generated in the high pressure chamber 35 is guided to the vane back pressure chamber 6 in the first and second suction regions through the back pressure ports 41 and 43.

  As shown in FIG. 5, a first suction port 65 is opened in the first suction region on the rotor front end surface 69 with which the rotor 2 in the pump cover 60 is in sliding contact, and the first discharge port is formed in the first discharge region. 66 opens, a second suction port 67 opens in the second suction area, and a second discharge port 68 opens in the second discharge area. The suction port 65 and the suction port 67 communicate with the tank 26 through the suction passage 25, and hydraulic oil from the tank 26 is guided.

  Four back pressure ports 61 to 64 are formed on the rotor front end surface 69 of the pump cover 60. Each of the back pressure ports 61 to 64 extends side by side in an arc shape with the rotation axis of the rotor 2 as the center, and communicates with each vane back pressure chamber 6. As shown by a two-dot chain line in FIG. 3, the first suction-side back pressure port 61 communicates with the vane back pressure chamber 6 that is expanded by the vane 3 that is in sliding contact with the first suction section 5A. The first discharge side back pressure port 62 communicates with the vane back pressure chamber 6 contracted by the vane 3 slidably contacting the first discharge section 5C. The second suction side back pressure port 63 communicates with the vane back pressure chamber 6 that is expanded by the vane 3 that is in sliding contact with the second suction section 5E. The second discharge-side back pressure port 64 communicates with the vane back pressure chamber 6 contracted by the vane 3 slidably contacting the second discharge section 5G.

  As the vane back pressure introducing means, the pump cover 60 has a back pressure communication passage 91 communicating with the first suction side back pressure port 61 and the first discharge side back pressure port 62, and a second suction side back pressure port. A back pressure communication passage 93 is formed to communicate 63 and the second discharge side back pressure port 64. As a result, the hydraulic oil in the vane back pressure chamber 6 contracting in the first discharge region expands in the first suction region through the discharge side back pressure port 62, the back pressure communication passage 91, and the suction side back pressure port 61. It flows into the chamber 6 and the vane 3 is prompted to protrude from the slit 8. The hydraulic oil in the vane back pressure chamber 6 that contracts in the second discharge region passes through the discharge side back pressure port 64, the back pressure communication passage 93, and the suction side back pressure port 63 to the vane back pressure chamber 6 that expands in the second suction region. The vane 3 is urged to protrude from the slit 8.

  The back pressure communication passages 91 and 93 are defined between a groove opened in the rotor front end surface 69 of the pump cover 60 and the end surface 21 of the rotor 2. The back pressure communication passages 91 and 93 are not limited to the configuration described above, and may be defined by through holes formed in the pump cover 60.

  A vane back pressure introduction restricting means for restricting that the vane back pressure guided to the second discharge side back pressure port 64 at the lower part of the rotor 2 is guided to the first suction side back pressure port 61 at the upper part of the rotor 2. Is provided. As the vane back pressure introduction restricting means, the second discharge side back pressure port 64 and the first suction side back pressure port 61 are not provided with a back pressure communication path therebetween, and the front side of the rotor slidably contacting the rotor 2 The end surface 69 blocks communication between the two. Similarly, the first discharge-side back pressure port 62 and the second suction-side back pressure port 63 are not provided with a back pressure communication path therebetween, and are communicated with each other by a rotor front end face 69 that is in sliding contact with the rotor 2. Is blocked.

The vane pump 1 is mounted in a posture that satisfies the following conditions.
The first suction section 5 </ b> A of the inner peripheral cam surface 5 is located above the second discharge section 5 </ b> G, and the discharge section 5 </ b> C is disposed above the suction section 5 </ b> E of the inner peripheral cam surface 5.
-The first suction / discharge transition section 5B of the inner circumferential cam surface 5 provided between the first suction area and the first discharge area, and the inner area provided between the second suction area and the second discharge area. The second suction / discharge transition section 5F of the circumferential cam surface 5 is arranged so as to be aligned in the vertical direction. That is, the first suction / discharge transition section 5B and the second suction / discharge transition section 5F are arranged so as to intersect with the same line extending in the vertical direction.

  As shown in FIG. 3, when the vane pump 1 takes an attitude that satisfies the above-described conditions, gravity is applied to the vane 3 located in the first suction region and the first discharge region in a direction that goes into the interior of the slit 8. work. On the other hand, gravity acts on the vane 3 located in the second suction region and the second discharge region in the direction in which the gravity protrudes from the slit 8. In FIG. 3, in the transition region where the first and second suction / discharge transition sections 5B and 5F are arranged vertically, the vane 3 extends in the vertical direction, so that the gravity acting on the vane 3 is maximized. In FIG. 3, in the transition region where the discharge suction transition sections 5D and 5H are arranged side by side, the vane 3 extends in the horizontal direction, so that the gravity acting on the vane 3 becomes minimum (zero).

  The posture of the vane pump 1 is not limited to the above-described configuration, and the first suction section 5A of the inner peripheral cam surface 5 is above the second discharge section 5G, and the discharge section 5C is the suction of the inner peripheral cam surface 5. If it is arranged above the section 5E, the imaginary line connecting the first and second suction / discharge transition sections 5B and 5F may be inclined to some extent with respect to the vertical line extending in the vertical direction.

  When the vane pump 1 is stopped, as shown in FIG. 3, the vanes 3 in the first suction region and the first discharge region fall into the interior of each slit 8 due to gravity, and the vane 3 and the cam ring 4 A pressure relief passage 39 is created which communicates the first discharge port 32 and the first suction port 31 through a gap defined therebetween. On the other hand, the vanes 3 in the second suction area and the second discharge area are projected from the slits 8 by gravity and maintained in contact with the inner peripheral cam surface 5.

  When the vane pump 1 is started, the pump chamber 7 contracts in the second discharge region, so that the pump discharge pressure guided from the second discharge port 34 to the high pressure chamber 35 is changed to the first as shown by an arrow A in FIG. If the one discharge port 32 escapes to the suction passage 25 through the pressure relief passage 39, it takes time for the discharge pressure in the high pressure chamber 35 to rise.

  In response to this, the vane pump 1 is provided with a check valve 70 at the first discharge port 32. The check valve 70 opens with respect to the flow of hydraulic oil discharged from the first discharge port 32 to the high pressure chamber 35, and with respect to the flow of hydraulic oil toward the first discharge port 32 from the high pressure chamber 35. Close the valve.

  In the circuit diagram of FIG. 1A, the flow of hydraulic oil during normal operation of the vane pump 1 is indicated by arrows. During operation of the vane pump 1 in which the rotor 2 rotates in the direction of the arrow, the vane 3 follows the cam ring 4 and enters the slit 8 in the first and second discharge regions, and the vane 3 in the first and second suction regions. The operation of protruding from the slit 8 following the cam ring 4 is repeated, and the pump chamber 7 is expanded and contracted. Accordingly, the hydraulic oil in the tank 26 is supplied to the pump chamber 7 through the suction passage 25, the first suction port 31, and the second suction port 33. On the other hand, the pressurized hydraulic fluid discharged from the pump chamber 7 is supplied to the hydraulic device 18 through the first discharge port 32, the second discharge port 34, the high pressure chamber 35, and the discharge passage 36 in order. At this time, the check valve 70 is opened for the hydraulic fluid flowing into the high pressure chamber 35 from the first discharge port 32. The hydraulic oil discharged from the hydraulic device 18 is returned to the tank 26 through the return passage 27.

  During the operation of the vane pump 1, the pump discharge pressure of the high pressure chamber 35 is led from the discharge pressure introduction passages 51, 53 to the vane back pressure chambers 6 through the back pressure ports 41, 43. It is urged in the direction protruding from.

  As described above, when the vane pump 1 is stopped, the vane 3 located at the top of the vane pump 1 falls into the interior of each slit 8 due to gravity, and the first discharge port 32 and the first suction port 31 communicate with each other. A pressure relief passage 39 is created. As the rotor 2 rotates in the direction of the arrow from this state, the vane 3 falls into the slit 8 and the pump chamber 7 is not defined in the first discharge region, so the first discharge port 32 is pressurized. The hydraulic oil is not guided and the check valve 70 is closed. On the other hand, in the second discharge region, the pump chambers 7 are defined by protruding from the respective slits 8 due to gravity, so that the vane 3 follows the inner peripheral cam surface 5 and enters the slits 8 so that the pump chambers 7 Shrinked. The pressurized hydraulic fluid discharged from the pump chamber 7 in the second discharge region thus contracting is guided to the high pressure chamber 35 through the second discharge port 34. At this time, since the check valve 70 is closed, the pump discharge pressure guided to the high pressure chamber 35 is prevented from escaping to the suction passage 25 through the first suction port 31 and the pressure relief passage 39. The pump discharge pressure in the high pressure chamber 35 rises quickly.

  FIG. 1B shows the flow of hydraulic oil at the time of starting of the vane pump 1 in which the pressure relief passage 39 is formed by arrows. The hydraulic oil in the tank 26 is supplied to the pump chamber 7 in the second suction region through the suction passage 25 and the second suction port 33. On the other hand, the pressurized hydraulic fluid discharged from the pump chamber 7 in the second discharge region is prevented from flowing back to the suction passage 25 through the first suction port 31 and the pressure relief passage 39 by the check valve 70. As a result, the pressurized hydraulic fluid discharged from the pump chamber 7 in the second discharge region is supplied to the hydraulic device 18 through the second discharge port 34, the high pressure chamber 35, and the discharge passage 36 in this order.

  When the vane pump 1 shown in FIG. 1B is started, on the side plate 30 side of the rotor 2, the pump discharge pressure of the high-pressure chamber 35 passes from the discharge pressure introduction passages 51, 53 through the back pressure ports 41, 43. Guided to the pressure chamber 6. The pressure guided to the back pressure port 41 urges the vane 3 that has fallen in the first suction region to protrude from the slit 8, and the pressure relief passage 39 disappears, thereby rapidly increasing the pump discharge pressure.

  When the vane pump 1 shown in FIG. 1B is started, on the pump cover 60 side of the rotor 2, the vanes 3 protrude from the slits 8 by gravity in the second discharge region. Follows and enters slit 8. The vane back pressure chamber in which the hydraulic oil in the vane back pressure chamber 6 contracted by the base end portion of the vane 3 expands in the second suction region through the discharge side back pressure port 64, the back pressure communication passage 93, and the suction side back pressure port 63. 6 and the pressure in the vane back pressure chamber 6 is increased.

  6A and 6B are cross-sectional views showing the check valve 70. The check valve 70 contacts the back surface 37 of the side plate 30 to close the discharge port 32, two pins 81 projecting from the back surface 74 of the valve body 71, and slides the pin 81. A guide hole 11 that supports the valve body 71 and a spring 82 that presses the valve body 71 against the side plate 30 are provided.

  The valve body 71 is formed in a plate shape having an end surface 73 that can come into contact with the back surface 37 of the side plate 30 and a back surface 74 that extends parallel to the end surface 73.

  The pin 81 has a circular cross section and a cylindrical side surface. The pin 81 is, for example, hardened and hardened, and a dowel pin having a predetermined dimensional accuracy is used. The pin 81 may be integrally formed with the valve body 71 without being limited to the configuration described above.

  The valve body 71 is formed with two fitting holes 75 opened in the back surface 74, and a cylindrical pin 81 is press-fitted into the fitting hole 75. The pin 81 protrudes from the back surface of the valve body 71 and extends in parallel with the rotation axis of the rotor 2.

  The pump body 10 is formed with two guide holes 11 into which the pins 81 are slidably inserted. The guide hole 11 is formed so as to extend in parallel with the rotation axis of the rotor 2. Thereby, the valve body 71 is supported so as to move in parallel via the pin 81.

  The guide hole 11 has a circular cross-sectional shape, and a gap between the guide hole 11 and the pin 81 is provided. Thereby, the pin 81 smoothly slides with respect to the guide hole 11, and the end surface 73 of the valve body 71 comes into contact with the back surface 37 of the side plate 30 without a gap.

  A coiled spring 82 is provided as an urging means for pressing the valve body 71 against the side plate 30. The spring 82 is compressed and interposed between the pump body 10 and the valve body 71. The pump body 10 is formed with a spring accommodating hole 12 in which a part of the coiled spring 82 is accommodated. On the other hand, a spring receiving portion 76 that opens to the back surface 74 of the valve body 71 is formed, and one end of a coiled spring 82 is seated inside the spring receiving portion 76. The spring accommodating hole 12 and the spring receiving portion 76 are formed so as to extend in parallel with the rotation axis of the rotor 2. As a result, the spring force of the spring 82 against the valve body 71 acts in a direction parallel to the pin 81.

  A guide hole communication path 14 that communicates the guide hole 11 and the high-pressure chamber 35 is provided. Thereby, when the check valve 70 is opened and closed, the working fluid in the guide hole 11 passes through the guide hole communication passage 14 and the high pressure chamber 35 as the pin 81 slides in the axial direction with respect to the guide hole 11. Go in and out.

  The pump body 10 is formed with two guide hole side slits 13 communicating with each guide hole 11 and the spring accommodating hole 12. Each guide hole side slit 13 and the spring accommodation hole 12 define a guide hole communication path 14 that communicates each guide hole 11 and the high-pressure chamber 35. Thereby, the flow path area of the guide hole communication path 14 is sufficiently secured in the axial direction of the guide hole 11. When the check valve 70 is opened and closed, the working fluid in the guide hole 11 passes through the guide hole side slit 13 and enters and exits the spring accommodating hole 12, and the pin 81 slides smoothly with respect to the guide hole 11. it can.

  Each of the guide hole side slits 13 opens in both the guide hole 11 and the spring accommodating hole 12, the distal end opening portion opens in a valve body facing surface 16 </ b> B of the pump body 10, which will be described later, and the base end surface thereof is the guide hole 11. And a portion connected to the bottom 12 </ b> A of the spring accommodating hole 12.

  When the pump body 10 is formed by casting, each guide hole 11, the spring accommodating hole 12, and each guide hole side slit 13 of the pump body 10 are formed by a mold. After casting the pump body 10, the guide hole 11 is cut. Since the spring housing hole 12 and each guide hole side slit 13 are not cut, the number of cuts applied to the pump body 10 is reduced, and the pump body 10 can be manufactured efficiently.

  FIG. 7 is a rear view showing the check valve 70 and the side plate 30. The valve body 71 is formed in a plate shape having an outer shape extending in the circumferential direction of the side plate 30 along the first discharge port 32 having a long hole shape. The valve body 71 extends in an arc shape around the rotation axis of the rotor 2 so as to face the first discharge port 32, and has an outer shape along the inner peripheral surface 30A and the outer peripheral surface 30B of the side plate 30.

  The spring 82 is disposed between the two pins 81 and faces the first discharge port 32 with the valve body 71 interposed therebetween. The spring receiving portion 76 is disposed between the two fitting holes 75, is aligned with the two fitting holes 75, and is disposed so as to have an equal interval between the two fitting holes 75.

  The inner wall surface 16 that defines the high-pressure chamber 35 of the pump body 10 includes an annular channel wall surface 16 </ b> A that defines an annular channel, and a valve body facing surface 16 </ b> B that faces the back surface 74 of the valve body 71.

  The annular flow passage wall surface 16 </ b> A of the pump body 10 is formed with a concavely curved cross section, and extends annularly around the rotation axis of the rotor 2.

  The valve body facing surface 16 </ b> B of the pump body 10 is formed in a planar shape substantially orthogonal to the rotation axis of the rotor 2 at a portion that protrudes from the annular flow wall surface 16 </ b> A toward the side plate 30.

  As shown in FIG. 6B, when the valve body 71 is in the valve opening position where the first discharge port 32 is opened, the back surface 74 of the valve body 71 abuts against the valve body facing surface 16B, and the end surface 73 of the valve body 71 and the side surface A channel having a predetermined width S is defined between the back surfaces 37 of the plate 30. At this valve opening position, the end surface 73 of the valve body 71 faces the back surface 37 of the side plate 30 substantially in parallel.

  As shown in FIG. 2, the inner wall surface 16 that defines the high-pressure chamber 35 of the pump body 10 has a discharge port-facing wall portion 16 </ b> C that faces the second discharge port 34. The discharge port facing wall portion 16 </ b> C is formed in a planar shape facing the back surface 37 of the side plate 30 substantially in parallel. The width of the flow path defined between the open end of the second discharge port 34 and the discharge port counter wall 16C is the flow defined between the end surface 73 of the valve body 71 and the back surface 37 of the side plate 30. It is formed equivalent to the width S of the road.

  A bottom portion (not shown) of the annular flow passage wall surface 16A of the pump body 10 is formed away from the back surface 37 of the side plate 30 from the valve body facing surface 16B, similarly to a discharge port facing wall portion 16D described later.

  Hereinafter, the operation of the check valve 70 will be described.

  When the vane pump 1 is stopped, as shown in FIG. 3, the vane 3 in the first discharge area and the first suction area falls into the interior of the slit 8, and the first discharge port 32 and the first suction port 31. The state where the pressure relief path 39 which connects these is created arises.

  When the vane pump 1 starts to rotate from the stopped state shown in FIG. 3, the valve body 71 is pressed against the side plate 30 by the biasing force of the spring 82, and the end surface 73 of the valve body 71 is the back surface 37 of the side plate 30. The first discharge port 32 and the high pressure chamber 35 are shut off.

  When the pressure of the first discharge port 32 rises as the rotor 2 rotates while the check valve 70 is closed, the valve body 71 is moved to the side by the pressure of the hydraulic oil discharged from the first discharge port 32. Move away from the plate 30. When the check valve 70 is opened in this way, the hydraulic oil is discharged from the first discharge port 32 to the high pressure chamber 35 as indicated by arrows in FIGS. 2 and 6B.

  When the valve body 71 moves against the spring force of the spring 82 due to the pressure of the hydraulic oil discharged from the first discharge port 32, the two pins 81 slide into the guide hole 11, thereby causing the valve body 71 is moved while maintaining the posture with respect to the side plate 30 by two pins 81. Thereby, the stroke which the valve body 71 moves with respect to the side plate 30 is fully ensured.

  During normal operation, as shown in FIGS. 2 and 6B, the back surface 74 of the valve body 71 contacts the valve body facing surface 16B, and the opening end of the first discharge port 32 (the back surface 37 of the side plate 30) A flow path having a predetermined width S is defined between the end face 73 of the valve body 71. Thereby, when the check valve 70 is opened, a sufficient cross-sectional area of the flow path defined between the valve body 71 and the side plate 30 is secured, and the check valve 70 increases the driving loss of the vane pump 1. It can be suppressed.

  On the other hand, a flow path having a predetermined width S is also defined between the opening end of the second discharge port 34 (the back surface 37 of the side plate 30) and the discharge port opposite wall portion 16C. Thereby, the pressures of the hydraulic oil discharged from the first discharge port 32 and the second discharge port 34 are equalized, and the pressure received by the rotor 2 from the first discharge port 32 and the second discharge port 34 is balanced. As a result, the occurrence of noise or the like from the vane pump 1 can be suppressed.

  According to the above embodiment, there exists an effect shown below.

  [1] The check valve 70 includes a valve body 71 that abuts the back surface 37 of the side plate 30 where the discharge port 32 opens and closes the discharge port 32, and a plurality of pins that protrude from the back surface 74 of the valve body 71. 81, a guide hole 11 formed so as to open toward the high-pressure chamber 35 and into which the pin 81 is slidably inserted, and a biasing means which is accommodated in the high-pressure chamber 35 and presses the valve body 71 against the side plate 30 Since the plurality of pins 81 slide into the guide holes 11, the valve body 71 moves while maintaining the posture with respect to the side plate 30, and the valve body 71 moves to the side plate 30. A sufficient stroke is ensured. Thereby, when the check valve 70 is opened, a sufficient cross-sectional area of the flow path defined between the valve body 71 and the side plate 30 is secured, and the check valve 70 increases the driving loss of the vane pump 1. It can be suppressed.

  [2] The urging means is a coiled spring 82, and the spring 82 is disposed between the two pins 81 so as to face the discharge port 32 with the valve body 71 interposed therebetween. The two pins 81 can move smoothly while maintaining the posture with respect to the side plate 30.

  In addition, not only the structure mentioned above but the valve body 71 is good also as a structure supported so that a movement is possible via three or more pins.

  [3] Since the guide hole communication passage 14 that communicates the guide hole 11 and the high pressure chamber 35 is provided, the working fluid in the guide hole 11 that expands and contracts as the pin 81 slides when the check valve 70 opens and closes is guided. The pin 81 can smoothly slide with respect to the guide hole 11 by entering and exiting the high-pressure chamber 35 through the hole communication path 14.

  [4] A spring accommodating hole 12 that is formed to open toward the high-pressure chamber 35 and accommodates the spring 82; and a guide hole side slit 13 that communicates the guide hole 11 and the spring accommodating hole 12; Since the hole communication path 14 is constituted by the guide hole side slit 13 and the spring accommodating hole 12, the flow path cross-sectional area of the guide hole communication path 14 is sufficiently secured, and the pin 81 slides smoothly with respect to the guide hole 11. Can move.

  The guide hole communication path 14 is not limited to the configuration described above, and may be formed by a through hole that communicates the guide hole 11 and the high pressure chamber 35.

  [5] The balanced vane pump 1 includes two discharge ports 32 and 34 that open to the high-pressure chamber 35, and the first discharge section 5C of the inner circumferential cam surface 5 is located above the second suction section 5E. The check valve 70 is provided in a first discharge region where the pump chamber 7 communicates with the suction side (suction passage 25) by the vane 3 that has fallen into the slit 8 at the time of activation. Since the valve is opened with respect to the flow of the working fluid discharged from the discharge port 32 to the high pressure chamber 35, the working fluid pressure generated in the pump chamber 7 is reduced by the slit 8 when the check valve 70 is closed at the time of activation. It is possible to suppress the escape to the suction side (suction passage 25) through the pressure relief passage 39 defined by the vane 3 that has fallen into the vane 3, and to increase the pump discharge pressure.

  In the balanced vane pump 1, the check valve 70 is connected to the discharge port 34 in the region (second discharge region) where the pump chamber 7 does not communicate with the suction side (suction passage 25) by the vane 3 falling into the slit 8 at the time of activation. Is not provided, the check valve 70 does not give resistance to the flow of the working fluid flowing into the high pressure chamber 35 from the discharge port 34, and an increase in driving loss of the vane pump 1 can be avoided.

  The check valve 70 may be provided in both the first and second discharge ports 32 and 34 without being limited to the above-described configuration. As a result, the above actions and effects can be obtained regardless of the direction in which the vane pump 1 is mounted.

  [6] A balanced vane pump 1 including a first discharge port 32 provided with a check valve 70 and a second discharge port 34 provided with no check valve 70, which defines a high-pressure chamber 35. A discharge port-facing wall portion 16C facing the second discharge port 34 is provided on the inner wall surface 16 and the flow path defined between the opening end of the second discharge port 34 and the discharge port-facing wall portion 16C is provided. Since the width is formed to be equal to the width S of the flow path defined between the open end of the first discharge port 32 and the valve body 71, the first discharge port 32 and the second discharge port 34 The pressure of the discharged hydraulic oil becomes uniform, and the occurrence of noise and the like from the vane pump 1 can be suppressed.

  In addition to the above-described configuration, as shown by a two-dot chain line in FIG. 2, a discharge port-facing wall portion 16 </ b> D that faces the second discharge port 34 is recessed in the inner wall surface 16 that defines the high-pressure chamber 35. Alternatively, the discharge port-facing wall 16D may extend without a step from the bottom of the annular flow wall 16A. Thereby, the width of the flow path defined between the opening end of the second discharge port 34 and the discharge port opposite wall portion 16D is increased, and the flow rate of the hydraulic oil discharged from the second discharge port 34 is increased. be able to.

  The present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.

  The vane pump of the present invention is not limited to a fluid pressure device mounted on a vehicle, and can be used as a fluid pressure supply source for driving a load of, for example, a construction machine, a work machine, another machine, or a facility.

1 vane pump 2 rotor 3 vane 5 inner peripheral cam surface 5A first suction section 5C first discharge section 5E second suction section 5G second discharge section 7 pump chamber 8 slit 11 guide hole 12 spring accommodating hole 13 guide hole Side slit 14 Guide hole communication path 16 Inner wall surface 16C Discharge port opposite wall portion 30 Side plate 31 First suction port 32 First discharge port 33 Second suction port 34 Second discharge port 35 High pressure chamber 37 Side plate Back surface 70 Check valve 71 Valve body 74 Back surface 81 Pin 82 Spring (biasing means)

Claims (6)

A vane pump used as a fluid pressure supply source,
A rotor that is driven to rotate;
A plurality of slits formed radially in the rotor;
A plurality of vanes slidably received in the slit;
An inner circumferential cam surface with which the tip of the vane is in sliding contact;
A pump chamber defined between the inner circumferential cam surface and the adjacent vane;
A suction port for guiding the working fluid sucked into the pump chamber;
A discharge port for guiding the working fluid discharged from the pump chamber;
A side plate in which the discharge port opens;
A high-pressure chamber for guiding the working fluid discharged from the discharge port to a fluid pressure supply destination;
A check valve that opens with respect to the flow of the working fluid discharged from the discharge port to the high-pressure chamber,
The check valve is
A valve body that abuts the back surface of the discharge port of the side plate and closes the discharge port;
A plurality of pins protruding from the back surface of the valve body;
A guide hole formed so as to open facing the high-pressure chamber and into which a pin is slidably inserted;
A vane pump comprising: an urging unit that is accommodated in the high-pressure chamber and presses the valve body against the side plate.   The said urging | biasing means is a coil-shaped spring, The said spring is arrange | positioned so that the said valve body may be pinched | interposed between two said pins, The discharge port may be opposed. Vane pump.   The vane pump according to claim 1, further comprising a guide hole communication path that communicates the guide hole with the high pressure chamber. A spring housing hole formed to open facing the high pressure chamber and housing the spring;
A guide hole side slit communicating the guide hole and the spring accommodation hole,
4. The vane pump according to claim 3, wherein the guide hole communication path includes the guide hole side slit and the spring accommodation hole. The inner circumferential cam surface is
The first and second suction sections in which the working fluid is sucked through the first and second suction ports as the rotor rotates,
The first and second discharge sections through which the working fluid is discharged through the first and second discharge ports as the rotor rotates,
The first suction section is located above the second discharge section, and the first discharge section is disposed above the second suction section;
5. The vane pump according to claim 1, wherein the check valve is opened with respect to a flow of the working fluid discharged from the first discharge port to the high pressure chamber. The first discharge port provided with the check valve;
The second discharge port not provided with the check valve,
A discharge port-facing wall portion facing the second discharge port is provided on the inner wall surface defining the high-pressure chamber,
The width of the flow path defined between the opening end of the second discharge port and the discharge port opposite wall portion is a flow defined between the opening end of the first discharge port and the valve body. The vane pump according to claim 5, wherein the vane pump is formed to be equal to a width of the passage.

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